enable_toolset

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare destructiveHint=false, so the description carries the real behavioral burden and delivers: it discloses the tools-list-changed notification side effect, the all-or-nothing revert on schema-budget breach (atomicity), and the refusal when SPOTIFY_MCP_READONLY hides a module. These are exactly the operational traits an agent needs and cannot get from the schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with the core action before the notification and failure semantics. The embedded vocabulary list is long but load-bearing; the em-dash clauses pack in a lot, keeping it slightly dense rather than wasteful.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a session-state-mutating tool, the description covers activation, the notification emitted, atomic rollback on budget breach, and the readonly refusal. An output schema exists, so return values need no explanation, and nothing an agent needs to invoke it correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, and the schema already enumerates the known sets and explains that 'all' selects every set, so the baseline is 3. The description's vocabulary list largely duplicates the schema's set names and adds no new syntax or format detail, so it earns no premium.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a precise verb+resource+scope: 'Register an inactive toolset into THIS session.' It names the concrete side effect (emitting the MCP tools-list-changed notification) and the goal (widen the surface without a restart), which cleanly distinguishes it from siblings like toolset_report or find_tool.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides clear context for when it applies ('widen the surface without a restart') and implicit exclusions (refuses modules hidden by readonly, reverts on budget breach). However it never names an alternative tool or states when a caller should prefer another route, so it stops short of full routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.